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Is there a Node module that can parse a specific number of records from a CSV file? The use case is to parse a large log file and deliver records to a paging client as requested.

node-csv can't yet do this, and the closest I've found is to read lines one by one, which requires reinventing the CSV parsing wheel, and will break on multi-line records.

But let's lower the bar: how can I parse single-line CSV records one by one with Node.js? Pretty trivial task in most other languages.

Is there a Node module that can parse a specific number of records from a CSV file? The use case is to parse a large log file and deliver records to a paging client as requested.

node-csv can't yet do this, and the closest I've found is to read lines one by one, which requires reinventing the CSV parsing wheel, and will break on multi-line records.

But let's lower the bar: how can I parse single-line CSV records one by one with Node.js? Pretty trivial task in most other languages.

• javascript
• node.js
• csv

Share Improve this question Follow edited May 23, 2017 at 12:13 CommunityBot 111 silver badge asked Oct 25, 2013 at 10:57 Dan DascalescuDan Dascalescu 152k6565 gold badges333333 silver badges420420 bronze badges 3

• You should consider writing one :) – SheetJS Commented Oct 25, 2013 at 22:57
• What do you mean by "single-line CSV records"? Because obviously it's not just 1 line, as my reply got downvoted. – Slavo Commented Oct 28, 2013 at 9:32
• @Slavo: no idea who downvoted your answer (wasn't me). By "single-line CSV records", I mean ma-separated tuples without newlines in any of the fields. As in, the regular type of CSV data. – Dan Dascalescu Commented Oct 28, 2013 at 11:56

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2 Answers 2

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As far as I understand, you just want to parse the ma-separated line of values into an array? If so, try this one:

https://npmjs/package/csvrow

Parsing a single 'line' (which can also have embedded newlines):

var csv = require('csv'); // node-csv

csv()
  .from.string(SINGLE_LINE_OF_CSV)
  .to.array(function(record) {
    console.log('R', record);
  });

I'm not sure what you mean by 'a specific number of records from a CSV file', or what the issue is exactly. Once you've read the amount you need, just send the response back to the client and you're done.

EDIT: if you want to implement paging, you can use node-csv too:

var csv   = require('csv');
var skip  = 100;
var limit = 10;

csv()
  .from.path('file.csv')
  .on('record', function(row, index) {
    if (index >= skip && index < (skip + limit))
      console.log('R', index);
  });

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